1. Field of the Invention
The present invention is directed to a process for the upgrading of olefinic stocks by sequential hydroformylation (HDF) and hydrogenation. Suitable feedstocks include FCC light cycle oil, products from distillate dewaxing, lube dewaxing, coker liquids, shale oil and pyrolysis gasoline.
2. Discussion of the Prior Art
Cracked stocks which have a significant proportion of olefins and diolefins normally contained therein are usually upgraded by hydrogenation to form saturated hydrocarbons. The present process employs synthesis gas (H.sub.2 +CO) to convert olefinic material in such stock to methylated, saturated hydrocarbons. Two sequential reactions are involved; hydroformylation of the olefins to alcohols followed by hydrogenation to saturates. These reactions coupled with steam reforming of methane produce more liquid hydrocarbon than is produced by hydrogenation alone. The resultant product is lower in pour point, and higher in viscosity index (V.I.) and thermal stability. Since the hydroformylation/hydrogenation steps do not occur by carbonium ion mechanisms, even stocks with high basic nitrogen (e.g., shale oil) can be methylated and are therefore suitable for use as a feedstock in the disclosed invention. Although the current process is drawn from known chemical reactions, the improved product, operating requirements and resultant increased yields of usable products are the direct beneficial effects of the specific integrated process disclosed herein.